Cells What is a cell Whats inside a

Cells What is a cell? What’s inside a cell? What are the differences between animal cells and plant cells.

What is a cell? • A cell is the smallest unit that is capable of performing life functions. • The cells theory states the following: – All living things are made up of cells. – All cells come from preexisting cells through cell division. Red Blood Cells Cheek (Skin) Cells Onion Cells

Examples of Cells Amoeba Proteus Plant Stem Bacteria Red Blood Cell Nerve Cell

What is inside a cell? • Cells are made up of • Some organelles are parts called organelles or only found in plant cells. “little organs”. – These include cell walls and chloroplasts. • The parts of a cell that – The vacuoles found in we are going to discuss plant cells are larger. include: – – – – Cell Membrane Cell Wall Nucleus Cytoplasm Chloroplasts Vacuoles Mitochondria

Cell Membrane • Surrounds a cell, allows certain materials to enter the cell and waste products to exit • Outer membrane of cell that controls movement in and out of the cell • Double layer http: //library. thinkquest. org/12413/structures. html

Cell Wall • Tough material surrounding the cell membrane in plant cells. • Most commonly found in plant cells & bacteria • Supports & protects cells http: //library. thinkquest. org/12413/structures. html

Nucleus • Directs cell activities • Separated from cytoplasm by nuclear membrane • Contains genetic material - DNA

Cytoplasm • All the material of the cell between the cell membrane and the nucleus • Gel-like mixture • Surrounded by cell membrane • Contains hereditary material

Mitochondria • The cell’s power producers. • Mitochondria combine oxygen and food to produce energy in the process of cellular respiration. • Controls level of water and other materials in cell l

Vacuoles • Membrane-bound sacs for storage, digestion, and waste removal • Contains water solution • Larger in plant cells • Help plants maintain shape by storing water http: //library. thinkquest. org/12413/structures. html

Chloroplast • Uses the energy in sunlight to turn water and carbon dioxide into sugar and oxygen (a process called photosynthesis) • Usually found in plant cells • Contains green chlorophyll http: //library. thinkquest. org/12413/structures. html

What are the differences between plant and animal cells? • Plant cells are much like animal cells, except for 3 important differences. – Plant cells have cell walls, which make them appear rectangular-shaped. These structures are composed of cellulose, hemicellulose, and a variety of other materials. – Plant cells have chlorophyll, the light-absorbing pigment required for photosynthesis. This pigment is contained in structures called chloroplasts, which makes plants appear green. – Plants cells have a large, central vacuole. While animal cells may have one or more small vacuoles, they do not take up the volume that the central vacuole does (up to 90% of the entire cell volume!). The vacuole stores water and ions, and may be used for storage of toxins.

Plant Cell vs Animal Cell

What am I, plant or animal?

Plant Cell Animal Cell

Pictures of cells Cancer cell being attacked by the immune system

Nerve Cells Cheek (Skin) Cells Liver Cells

A plant cell from the leaf of a poplar tree Plant cell with nucleus very visible Seaweed under a microscope

Stomach Cells Cardiac Muscle (Heart) Cells Muscle Cells Bone Cells

Very thin slice of plant skin Orchid (flower) cells Leaf Cells of Moss Cells in a plant root

Case 21 Review

The correct answer is A • If you look at Cell 2, not only is it more box like but it also has a cell wall. That is how you know that is belongs to a plant. It could not be an animal cell

Let’s Try Another

The correct answer is A Cheek cells could be found in an animal. Animal cells are usually rounder with a thin outer membrane

How about this…

The correct answer is B • Cell Walls are only found in plant and bacteria cells. Animal cells do not have cell walls, but they do have all of the other organelles that are listed as the answer choices.